The earth produces a great quantity of plant organic material having little use or value today. Substantially all plant organic material includes the combination of cellulose and lignin in various compositions and structural arrangements. Lignin is an amorphous polymeric substance normally necessary in a plant or parts of a plant requiring rigidity, such as in any plant having stems, branches or a trunk. The lignocellulose material is digestable at varying efficiencies by different animals. For instance, grass which has a low order of cellulose lignin bond, is readily digestably by ruminants. Humans, however, connot digest grass at a sufficiently high level to maintain body weight and therefore must depend upon a high order of digestable organic material, such as grain. Other animals, such as beavers, can successfully digest wood pulp material, like tree bark, at a sufficient rate to maintain growth whereas agricultural livestock such as cattle, sheep, horses and swine, cannot subsist on a diet of tree bark.
Even among agricultural animals the digestible systems vary to an extent wherein cattle can effectively utilize plant organic material having a lignin cellulose composition which will not be useful for swine.
The world today faces imminent famine. The human population has grown at such a rate that the grain producing potential of the world is being overtaxed. The diversion of grain to agricultural animals to produce meat results in a net calorie loss in terms of human food consumption. The impending famine exists in spite of a huge quantity of plant organic material in the forests and jungles of the world. If the digestability of plant organic material can be increased significantly the forests and jungles can produce sufficient food for the world's increasing population.
It is an object of this invention to provide a means of increasing the digestability of plant organic material by animals.
More particularly, an object of this invention is to provide a process of treating plant organic material to weaken at least part of the lignin-cellulose bond to expose increased portions of the cellulosic content to consumption by the digestive system of animals and to partially hydrolyze the exposed cellulose to its sugar monomers and to convert some of the sugars to their easily digested acids of oxidation.
Still more particularly, an object of this invention is to provide a process of treating cellulose bearing plant organic matter with nitric acid in a cooking process to break down the lignin-cellulose bond, thereby exposing the cellulosic component to digestable consumption by agricultural animals.
These general objects, as well as other and more specific objects of the invention will be fulfilled in the following description and claims, taken in conjunction with the attached drawing.